Resumption token not read about oai-pmh

[andrenarchy]

Thank you for reporting the issue! This might be a problem with how xml2js parses the returned XML – or possibly the ._ is just wrong :). Can you check how it works with another OAI PMH provider? I never experienced any problems but maybe the ones I used don't use resumption tokens...

[danmichaelo]

Goodness, _ contains the character content (see "charkey" at https://github.com/Leonidas-from-XIV/node-xml2js) if the element has attributes.

So it works for repositories that returns

<resumptionToken completeListSize="119657" cursor="0">oai_dc////100</resumptionToken>

but not for

<resumptionToken>oai_dc////100</resumptionToken>

The completeListSize and cursor attributes are not required by the OAI-PMH spec, so some repos provide them, others not. xml2js has an option called explicitCharkey, which I guess makes sure _ is always there, but that could probably also mess up lots of other things? What do you think about just adding a fallback?

resumptionToken: self.currentResult.resumptionToken._ || self.currentResult.resumptionToken,

[andrenarchy]

Jeez, you never stop learning what could go wrong when parsing XML... ;)

I think explicitCharkey makes sense. The object structure should really be independent from the presence of attributes. I don't have time to test this myself right now (or in the next 2 days) but of course I'm happy to review a PR if you have time to do it!

[danmichaelo]

Don't think I'll be able to pull together a PR. Made a quick attempt of setting explicitCharkey though, but then everything stopped working :D Or well, I got zero results. Guess some more ._s have to be sprinkled around the code first for it to work.

[andrenarchy]

I tried to test it here but unfortunately the URL in your original post leads to a 403 HTTP error with the following message:

Unauthorized access to the OAI services – please contact the system administrator for assistance

[danmichaelo]

This one should work I think:

oai-pmh list-records -p marc21 -s oai_komplett http://bibsys-network.alma.exlibrisgroup.com/view/oai/47BIBSYS_NETWORK/request